It has often been observed that certain appliances, particularly household appliances, must incorporate a safety switch sensitive to a shock exerted on the appliance or to an inclination of the latter, so as to cut off the supply to the appliance. In particular, where a portable electric radiator is concerned, there is a considerable risk of fire if the electric radiator is tipped against inflammable articles or placed on a surface which is not flat, so that the heating element is located near an inflammable article.
Safety switches known hitherto usually comprise a pendulum associated with electrical contacts arranged in the supply circuit, to make a connection between these contacts when the appliance is in the normal position of use, and to break the supply circuit when the appliance experiences a shock beyond a predetermined threshold or is inclined beyond a predetermined threshold according to the characteristics of the appliance.
It is also known to produce safety switches incorporating a sensitive element in the form of a ball normally arranged above a switch of the push-button type for closing the electrical supply circuit in the normal position of the appliance. When the appliance experiences a shock or is inclined, the ball escapes and releases the push-button which opens the electrical supply circuit. This type of safety switch has a cost price less than that of safety switches incorporating a pendulum, since the cost price of the ball is usually substantially below the cost price of a pendulum. However, the disadvantage of these switches is that they cannot be reset. In fact, when the push-button has come out and the appliance has been returned to its normal position, the ball comes up against the side of the push-button and therefore cannot act on the latter to reclose the switch. The switch consequently has to be reset manually, and this presents problems for users who are not familiar with the technique.